The present invention relates to a system, apparatus and method for evaluating a variety of protocols on a computer network which includes a plurality of network devices. The network devices are adapted to communicate messages on the computer network using their respective protocols. The present invention system, apparatus and method are associated with one of the network devices. The present invention system, apparatus and method are further adapted to identify the various protocols on the network and analyze each message on the network to determine the protocol associated with the message. Such an arrangement allows for a mixed mode communication on a single network.
The present invention system, apparatus and method may be used with a device associated with any type of computer network. Suitable computer networks may include local area networks (LANs), wide area networks (WANs), or any other computer networks which include a plurality of network devices which send messages therebetween using various protocols.
An example of a computer network is a Supervisory Control and Data Acquisition (SCADA) system. A SCADA system is typically a large-scale, distributed measurement and control computer network which includes a plurality of network devices which communicate using various protocols. The network devices of a typical SCADA system generally comprise a SCADA server for monitoring, controlling or automating one or more remotely connected Intelligent Electronic Devices (IEDs).
In one application, a SCADA system may be used in the monitoring, controlling and/or automation of an electric power system. Accordingly, a SCADA server may be used to monitor, control and/or automate IEDs such as electric power system protective devices, protective relays, remote terminal units (RTUs), power line communication devices, bay controllers, meters, and any other comparable devices. For example, a SCADA server may be adapted to control an IED to isolate some power system element(s) from the remainder of the power system upon detection of an abnormal condition or a fault in, or related to, the power system element(s).
In a typical SCADA system, the network devices associated therewith use various protocols which are often governed by protocol standards (e.g., MODBUS or DNP). Protocol standards govern how data is to be organized in a message such that the network devices are able communicate with one another. Because of these standards and for sake of ease, it has traditionally been preferable for SCADA systems to be configured such that all network devices communicate using the same protocol. For simple applications, the configuration of such systems is relatively easy as the SCADA server is merely required to communicate with one type of IED to perform a particular function.
In contrast, for complex applications such as networking of devices for an electric power system, it is preferable to configure a SCADA server for communication with many types of IEDs for the complete automation, controlling and/or monitoring of the system. These different IEDs in a SCADA system for an electrical power system are often multi-functional and, therefore, generally communicate using many different protocols. In traditional arrangements, the SCADA system is configured such that each protocol is transferred using separate communications lines, thereby forming multiple computer networks. This arrangement is particularly cumbersome and requires time- and labor-intensive configuration of the SCADA server and/or IEDs during installation. Therefore, it is an object of the present invention to provide a system and method for providing mixed-mode communication on a single network.
In another application, it is often preferable for the computer network to be encrypted for security purposes. However, it is often desirable to encrypt messages associated with some network devices and not others. Therefore, in such networks, it is often desirable to couple network devices using encrypted communication together, creating an encrypted network. Likewise, it is often desirable to couple network devices using non-encrypted communication together, creating a non-encrypted network. This arrangement is also particularly cumbersome and requires time and labor intensive configuration of the devices during installation.
Accordingly, it is an object of this invention to provide a system and apparatus that evaluates a variety of protocols on a computer network which comprises a plurality of devices that communicate using various protocols. It is further an object of the present invention to provide a system and apparatus which identifies the various protocols on the network and analyzes each message on the network to determine the protocol associated with the message. This arrangement allows all network devices, although adapted to communicate using different protocols, to reside on a single network or even on a single communications line. Such an arrangement allows for a mixed-mode communication on a single network or a single communications line.
These and other desired benefits of the preferred embodiments, including combinations of features thereof, of the invention will become apparent from the following description. It will be understood, however, that a process or arrangement could still appropriate the claimed invention without accomplishing each and every one of these desired benefits, including those gleaned from the following description. The appended claims, not these desired benefits, define the subject matter of the invention. Any and all benefits are derived from the multiple embodiments of the invention, not necessarily the invention in general.